11.   Doctors say it is largely preventable, because most colorectal cancers develop slowly over many years from benign polyps.

12.   For breast cancer, the most effective measure by far is to have both breasts removed before any cancer develops.

13.   However, only five cancers have developed in women who have fewer than two relatives in their family history of breast cancer.

14.   In addition, cancer can develop over such long periods that much of the evidence may be buried in the deep past.

15.   More importantly, Osborne said, are the new clues into how breast cancer develops that this discovery could provide.

16.   Most cancers had been developing for years in the body before they were diagnosed during which they turned the immune response off.

17.   Prostate cancer also develops earlier in African-American men.

18.   Rapid cell growth, in turn, increases the chances of genetic mutations that may allow a cancer to develop and grow unchecked.

19.   Researchers also hope to learn how cervical cancer develops by studying women with AIDS.

20.   Rapid cell growth can increase the chances of genetic mutations that may allow a cancer to develop and grow uncontrolled.